Autor: neq (neq_at_ags.pl)
Data: Fri 10 Mar 2000 - 00:45:20 MET
Piotr Kucharski <chopin_at_sgh.waw.pl> writes:
> neq <neq_at_ags.pl> wrote:
> >> Taka sytuacja Z PEWNOŚCIĄ powoduje problemy. Tylko nie dla wszystkich
> >> (protokołów znaczy) ;)
> > Huh, na ktorych protokolach Ci zalezy?
> Na mechanizmie PMTU discovery mi zależy.
RFC1191 (Sorry za doslowny cytat [paste], ale nie ujalbym tego lepiej):
"[...]
Note: The Path MTU is what in [1] is called the "Effective MTU
for sending" (EMTU_S). A PMTU is associated with a path,
which is a particular combination of IP source and
destination address and perhaps a Type-of-service (TOS).
[...]
A host doing PMTU Discovery must obey the rule that it not send IP
datagrams larger than 576 octets unless it has permission from the
receiver. For TCP connections, this means that a host must not
send datagrams larger than 40 octets plus the Maximum Segment Size (MSS)
sent by its peer.
[...]
-----------
Hm, zobaczmy.
~ > hostname
somewhere.in.lublin.pl
~ > ifconfig eth0
[ciach]
UP BROADCAST RUNNING MULTICAST MTU:576 Metric:1
[ciach] ^^^^^^^
~ > ping -s 10000 195.205.87.223
PING 195.205.87.223 (195.205.87.223): 10000 data bytes
10008 bytes from 195.205.87.223: icmp_seq=0 ttl=247 time=454.3 ms
10008 bytes from 195.205.87.223: icmp_seq=1 ttl=247 time=638.6 ms
10008 bytes from 195.205.87.223: icmp_seq=2 ttl=247 time=642.1 ms
10008 bytes from 195.205.87.223: icmp_seq=3 ttl=247 time=537.0 ms
[ciach]
--- 195.205.87.223 ping statistics ---
79 packets transmitted, 79 packets received, 0% packet loss
round-trip min/avg/max = 217.7/426.4/741.8 ms
> p.
Pozdrawiam ;)
-- "Bezczynni adwokaci maja sklonnosci [ neq_at_ags.pl / AGS New Media ] do zostawania politykami, totez utrzymywanie adwokatow w ciaglym zatrudnieniu ma pewne spoleczne znaczenie" // Silberschatz / Galvin // "Podstawy Systemow Operacyjnych"
To archiwum zostało wygenerowane przez hypermail 2.1.7 : Wed 19 May 2004 - 16:29:58 MET DST